• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.51
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• pp.151-161
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• 1999

For many decades, Deterministic DCF approach has been widely used to evaluate investment opportunities. Under new manufacturing conditions involving uncertainty and risk, the DCF approach is not appropriate. In DCF, Risk is incorporated in two ways: certainty equivalent method, risk adjusted discount rate. This paper proposes a determination method of the Risk Adjusted Discount Rate for economically decision making advanced manufacturing technologies. Conventional DCF techniques typically use discount rate which do not consider the difference in risk of differential investment options and periods. Due to their relative efficiency, advanced manufacturing technologies have different degree of risk. The risk differential of investments is included using $\beta$ coefficient of capital asset pricing model. The comparison between existing and proposed method investigated. The DCF model using proposed risk adjusted discount rate enable more reasonable evaluation of advanced manufacturing technologies.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1201-1206
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• 2008

Psychrometric chart displays graphically the thermophysical properties of moist air, so it is very conveniently used in air-conditioning and refrigeration. On general psychrometric chart, there are dry bulb temperature, web bulb temperature, absolute humidity ratio, relative humidity, specific enthalpy, specific volume, sensible heat factor, and enthalpy-humidity difference ratio. However, various state and process values besides aboves can be plotted on psychrometric chart. In this study, we developed the software drawing twenty kinds of lines, that is vapor pressure, mole fraction ratio of vapor, dew point temperature, degree of saturation, density, specific entropy, specific exergy, contact or bypass factor, uncomfort index, discomposition index, predicted mean vote index, predicted percent dissatisfied, and so on. We wish to this software is a help to design, analysis and education.

• Journal of Power System Engineering
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• v.1 no.1
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• pp.98-105
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• 1997

In general, crankshafts which are used in internal combustion reciprocating engines are subjects to high torsional vibration. Therefore, a damper is often used to minimize the torsional vibration in reciprocating engines. In this paper, in order to investigate damping performance of viscous damper, the real effective viscosity and complex damping coefficient of silicone oil, and the effective inertia moment of inertia ring are calculated considering the relative motion between damper casing and inertia ring. Based on these results multi-cylinder shaft is modeled into equivalent 2-degree of freedom system and optimum condition is estimated by calculating the amplification factor of viscous damper. Also the test damper was manufactured according to the result of theoretical investigation, the performance and durability was ascertained through experimental examination.

• Journal of the Korean Chemical Society
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• v.15 no.2
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• pp.85-93
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• 1971

Apparent molal valumes ${\phi}_v$ and relative viscosities ${\eta}_r$ of aqueous solutions of anilinium chloride have been determined at two degree intervals from 20 to $50^{\circ}C$ in the molar concentration range 0.003 < C < 0.4. The results are discussed in terms of partial molal volumes $\={V}^{\circ}$, deviations from the Debye-H$\''{u}$ckel limiting law, partial molal expansibilities $\={E}^{\circ}$, viscosity B coefficients calculated from the Jones-Dole equation, and energy of activation for viscous flow. In aqueous solution, anilinium chloride was found to be a weak structure-maker due to its hydrophobic group.

• 보존과학연구
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• s.17
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• pp.48-64
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• 1996

We compared the degree of color difference formed by environmental factor(temperature, relative humidity) with fungal growth in order to know how to change the color difference of cellulolutic cultural properties such as Korean papers, cotton, jute and hemp. We concluded, from the result, that the action of fungal growth on celluloytic cultural properties was more hamful than environmental factor. We considered the secretion produced by fungi as the causative agent for stained formation on cellulolytic cultural properties. Alternaria sp. colored allmaterials greyish black, Chaetomium sp. colored cotton and hemp orange, and Penicllium sp. colored cotton, jute and hemp yellowish green. But Trichoderma sp. and Aspergillus sp. didn't show a clear color against each material. It was observed that thymol(120g/$m^3$) was the most effective fungicide to prevent fungal growth.

• Journal of the military operations research society of Korea
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• v.26 no.2
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• pp.55-74
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• 2000

A knowledge-based with production rules is a representation of static knowledge of an expert. On the other hand, a real system such as the stock market is dynamic in nature. Therefore we need a method to reflect the dynamic nature of a system when we make inferences with a knowledge-based system. This paper suggests a strategy of dynamic inference that can be used to take into account the dynamic behavior of decision-making with the knowledge-based system consisted of fuzzy production rules. A degree of match(DM) between actual input information and a condition of a rule is represented by a value [0,1]. Weights of relative importance of attributes in a rule are obtained by the AHP(Analytic Hierarchy Process) method. Then these weights are applied as exponents for the DM, and the DMs in a rule are combined, with the Min operator, into a single DM for the rule. In this way, the importance of attributes of a rule, which can be changed from time to time, can be reflected in an inference with fuzzy production systems.

• Journal of Microbiology
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• v.43 no.6
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• pp.487-492
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• 2005

This study demonstrated that the brown rot basidiomycete Fomitopsis palustris was able to degrade crystalline cellulose (Avicel). This fungus could also produce the three major cellulases (exoglucanases, endoglucanases, and $\beta-glucosidase$) when the cells were grown on $2.0\%$ Avicel. Avicel degraded by F. palustris showed a decrease in relative crystallinity from $83\%\;to\;78.5\%$ after 14 days of incubation. The characterization study indicated that optimum pH was 4.5 and optimum temperature was $70^{\circ}C$ for exoglucanase (cellobiohydrolase) activity. Hydrolysis of Avicel by the crude enzyme from F. palustris yielded 1.6 mg/ml of glucose after 43 h, which corresponded to a cellulose conversion degree of $3.2\%$. Therefore, this study revealed for the first time that the brown rot basidiomycete F. palustris produces cellulases capable of yielding soluble sugars from crystalline cellulose.

• Korean Journal of Child Studies
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• v.21 no.4
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• pp.35-50
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• 2000

The objective of this research was to determine the relative impact of demographic variables and ecological factors on the parenting stress of dual earner families. Subjects were 318 fathers and 405 mothers who completed the questionnaire on parenting stress and ecological factors. Results showed that mothers perceived high parenting stress compared with fathers. Degree of satisfaction with child care was a significant correlate of parenting stress. Demographic and ecological factors were also important in understanding the variation in parenting stress of dual earner families. These findings imply that the formal child care systems and parent education programs are needed for working parents.

• Journal of the Korea Safety Management & Science
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• v.8 no.4
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• pp.205-218
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• 2006

Multi-criteria decision making is deducing the relative importance in the criterion of decision making and each alternative which is able to making a variety of choices measures the preferred degree in the series of town ranking criterions. Moreover, this is possible by synthesizing them systematically. In general, a fundamental problem decision maker solve for multi-criteria decision making is evaluating a set of activities which an considered as the target logically, and this kind of work is evaluated and synthesized by various criterions of the value which a chain of activities usually hold in common. In this paper, we use the compensatory models for the optimal decision making. For the purpose of optimal decision making, the data of five different car models are used in Europe.

• Journal of Family Resource Management and Policy Review
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• v.3 no.2
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• pp.105-123
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• 1999

The purpose of this study was to identify housewives’housing values, to explore the degree of housewives’housing satisfaction according to residential area and to investigate the relative importance of housing values which affect housewives’housing satisfaction according to residential area and socio-demographic variables. The subjects of this study were 1,984 married women living in Taegu. A questionnaire was used as survey method. The data was analyzed by means of factor analysis, ANOVA, Scheffe test and regression analysis. The main findings were as follow: First, there was significant difference in housewives’housing values according to residential area. Second, housewives’housing satisfaction was found to be significantly different according to residential area. Third, housewives’housing satisfaction was significantly affected by housing values according to residential area and socio-demographic variables.